Clinico-pathologic factors and survival of patients with breast cancer diagnosed with de novo brain metastasis: a national cancer database analysis.

PURPOSE: Patients with Breast Cancer (BC) with Brain Metastasis (BCBM) have poor survival outcomes. We aimed to explore the clinico-pathologic and therapeutic factors predicting the survival in patients with de novo BCBM using the National Cancer Database (NCDB).

PATIENTS AND METHODS: The NCDB was queried for patients with BC between 2010 and 2020. Survival analysis with Kaplan-Meier curves and log rank tests were used to find median overall survival (OS) in months (95% CI) across the different variables. A multivariate cox regression model was computed to identify significant predictors of survival.

RESULTS: Out of n = 2,610,598 patients, n = 9005 (0.34%) had de novo BCBM. A trend of decreasing OS was observed with increasing age, Charlson-Deyo score (CDS), and number of extracranial metastatic sites. The highest median OS was observed in the Triple Positive and the lowest OS in the Triple Negative subgroup. Based on treatment regimen, combination of systemic therapy and local therapy achieved the highest OS. A positive trend in OS was observed in the BC subgroup analysis with targeted therapy demonstrating a survival benefit when added to systemic therapy. The multivariate cox regression model showed that age, race, ethnicity, insurance, median income, facility type, CDS, BC subtype, metastatic location sites, and treatment combinations received were significantly associated with risk of death. Receiving only local treatment for BM without systemic therapy more than doubled the risk of death compared to combining it with systemic therapy.

CONCLUSIONS: This analysis suggests that treatment of systemic disease is the major factor influencing survival in patients with BCBM. Moreover, targeted therapy with anti-HER2 increased survival when added to systemic therapy explaining the highest median OS noted in the Triple Positive subgroup.